World Wide Web
Definitions Edit The World Wide Web (www) (also called simply the Web) is History Edit In 1990, the Web's main architect, Tim Berners-Lee, a programmer at CERN, the European Particle Institute in Geneva, Switzerland, collaborated with colleague Robert Caillau on the design document that explained hypertext as a way to link and access information. It described how documents could be interwoven in a network of links called a web. The 1990 document discussed notions fundamental to the Web as it is known today: the ability of links to cross computer or network boundaries; a common protocol for exchanging documents (Hypertext Transfer Protocol, or HTTP); a common document protocol for information suppliers and customers (Hypertext Markup Language, or HTML); support for index searches; the ability to view these documents with text or graphics browsers; and the location of pages of information by means of Uniform Resource Locators (URLs). The Web marked the merger of three different strands of innovation: Personal computing, networking, and connective software. In 1992, the Web was text-based, relatively unknown outside of academia, and used mainly by engineers, scientists, and computer hobbyists. In the spring of 1993, a software program called Mosaic was developed. It allowed users to view both text and graphics. The World Wide Web and the Internet are often confused by the public. But in reality, the World Wide Web is a system of linked documents and files, which operates over and is accessible by means of the Internet, but is entirely distinct from the network of networks, the Internet itself. Indeed, many other forms of communication, such as Internet Relay Chat (IRC), or Voice over IP (VoIP), using different protocols, co-exist with the World Wide Web on the Internet. Overview Edit The Web has two primary features that make it a powerful, "full service" method of accessing information through the Internet. First, Web clients, or browsers, can combine text and graphical material, and can incorporate all of the other major Internet services such as FTP, email, and news into one standard interface. Second, the Web incorporates a hypertext system that allows individual Web pages to provide direct links to other Web pages, files, and other types of information. Thus, full-scale user interfaces and complex services such as online shopping, continuously-updated news information, and videogames can be provided through the Internet over a non-proprietary system. The Web thus forms the foundation for virtually all Internet-based services. “The Web is what is known as a distributed system. The Web was designed so that organizations with computers containing information can become part of the Web simply by attaching their computers to the Internet and running appropriate World Wide Web software. No single organization controls any membership in the Web, nor is there any centralized point from which individual Web sites or services can be blocked from the Web. Documents available on the Web are not collected in any central location; rather, they are stored on servers around the world running Web server software. To gain access to the content available on the Web, a user must have a Web ‘browser’ — client software, such as Netscape Navigator, Mosaic, or Internet Explorer, capable of displaying documents formatted in "hypertext markup language" ("HTML"), the standard Web formatting language. Each document has an address, known as a Uniform Resource Locator ("URL"), identifying, among other things, the server on which it resides; most documents also contain "links" — highlighted text or images that, when selected by the user, permit him to view another, related Web document. Because Web servers are linked to the Internet through a common communications protocol, known as "hypertext transfer protocol" ("HTTP"), a user can move seamlessly between documents, regardless of their location; when a user viewing a document located on one server selects a link to a document located elsewhere, the browser will automatically contact the second server and display the document. Some types of Web client software also permit users to gain access to resources available on FTP and gopher sites.